CONSTRUCT-VALIDITY OF STAGES OF CHANGE FOR EXERCISE BEHAVIOR

Purpose. Previous research examining the transtheoretical model of beh avior change within the exercise do-main has been limited by use of se lf-report measures exclusively and inconsistent practices with regard to stage of exercise assessment. The present study was designed to par tially circumvent these limitations and extend the current literature by determining the degree of association among stage of exercise and b ody mass index, cardiorespiratory fitness, exercise behavior relapse, barriers, and self-efficacy, after controlling for several potential c onfounders. Design. A descriptive, cross-sectional study. Subjects. Tw o hundred thirty-five adults (M age = 34.7 years) volunteered to parti cipate. Measures. Participants were classified by stage of exercise an d compared on two behavioral, two biometrical, and three psychological variables while statistically controlling for social desirability and demographic differences. Results. Significant between-stage differenc es were found for the overall set of dependent variables (p <.0001) an d for each dependent variable separately (p <.01). The proportion of v ariance accounted for by the dependent variables ranged from .06 to .5 3. Conclusions. This study offers objective support for the stage-of-c hange model within the exercise domain. By acknowledging and accuratel y assessing stage of exercise, researchers and clinicians may be able to improve physical activity promotion efforts.